Electrical and electronic devices which can be operated independently of a power supply system are increasingly being used at the present time. In this case, ever more powerful rechargeable batteries are required on account of ever more powerful devices and the desire to provide as long an operating time as possible. Said rechargeable batteries should generally be as small and lightweight as possible yet have a high energy content. Great efforts have recently been made in order to be able to meet these contradictory requirements which arise in the construction of electric motor vehicles in particular. Nonetheless, there is still potential for improvement in the field of rechargeable battery technology.